Combined shutter and diaphragm mechanism for cameras



Dec. 15, 1953 M. N. FAIRBANK COMBINED SHUTTER AND DIAPHRAGM MECHANISM FOR CAMER 2 Shaets-$heet 1 Filed Nov. 4, 1948 9 amm mm oh INVENTOR M. N. FAIRBANK 2 Sheets-Sheet 2 Dec. 15, 1953 Filed Nov. 4, 1948 INVIENTIOR BY Patented Dec. 15, 1953 PATENT OFFICE COIHBINED SHUTTER AND DIAPHRAGM MECHANISM FOR CAMERAS Murry N. Fairbank, Belmont,

Mass., assignor to Polaroid Corporation, Cambridge, Mass., a corporation of Delaware Application November 4, 1948, Serial No. 58,258

6 Claims.

This invention relates to photography and more particularly to improvements in camera shutter and diaphragm assemblies.

A principal object or" the present invention is to provide an improved shutter and diaphragm assembly which is simple and to manufacture and assemble.

Another object of the present invention is to provide a shutter comprising a rotatably mounted shutter blade and including an improved means for calibrating the means which control speed with which the shutter blade is rotated.

Still another object of the present invention to provide, in a shutter assembly, a novel exposure synchronizing means. 15

A further object of the invention is to improved means for rotating a shut-t the above general type.

Still another object of the present invention is to provide, in a shutter of the having a 20 shutter blade which rotates at a substantially constant velocit an Lcprovec means for controlling the degree of rotation thereof and therecontrolling the exposure time.

Still another object of the invention is to provide improved means for holding the shutter blade in its aperture-uncovering position when time exposures are to be made.

These and other objects of t e invention will in part be obvious and will in part appear here inafter.

The invention accordingly cor ratus possessing the construetion, of elements and arrangezn ch are exemplified in the following detailed disclosure, and the scope or" the application or" which will o indicated in the claims.

For a fuller understanding of tie nature an objects of the invention, reference should be to the following detailed riescription to .811 connection with the (ll. wherein:

Figure l is a diagrammatic plan iew of a preferred form of the shutter and senzbly of the present invention, ti. and its associated lens ele' Fig. 1 and the shutter e. sly the focal plane of the camera;

Fig. 2 sectional view of the line 2- but additionally show I housing and the rear lens elements opcrative position;

a fragmentary view of the s .utter and diaphragm assembly of Fig. l with. the elemerits thereof positioed so that the shutter blade is just about to be rotated;

Fig. 4. is a fragmentary plan View of the shutter and diaphragm assembly of 1 where the shutter has just been rotated; and

Fig. 5 is a fragmentary sectional View of the shutter and diaphragm assembly of Fig. 1 taken along the line 55 of Fig. 1.

In general this invention merits in novel shutter and diaphragm assemblies of the general type described in the oopending application of Murry N. Fairbar and Sidney B. Whittier, Serial No. 727,092, filed February 7, 194.? (now Patent No. 2,531,936). In the preferred. form of the invention the shutter blade is supported in operative relation to exposure aperture, the shutter blade normally covering this aperture. The shutter blade is mounted so that it can be given an aperture-uncovering movement, this mounting preferably comprising a rela tively friction-free bearing, the shutter being preferably free to rotate through an arc of ap proximately 300. For imparting this apertureuncovering motion, preferably a rotary motion, to the shutter blade, there is provided an impulse member or kicker which, in turn, is energized by a spring. The kicker is normally held in an inoperative position by a latch, the kicker spring being stressed when the kicker is so held. A tripping le' er is arranged to release the kicker latch, thereby permitting the kicker to strike a portion of the shutter blade and to rotate this shutter blade at a substantially constant speed around its bearing from its stationary position to a position Where the exposure aperture is uncovered. The extent of rotation of the shutter blade is then controlled so as to control the time during which the aperture uncovered. In a preferred form, the shutter blade continues to rotate until a portion thereof hits a reversing means, this reversing means returning the shutter blade to aperturewovering position. A pre ferred type of reversing comprises a bounce spring, this bounce spring intercepting and reversing the shutter blade at a predetermi d point in its rotary travel. Thus the time du: ng which the exposure aperture is uncovered depends upon the speed arcuate travel of the shutter blade, this arcuate travel being preferably controlled by using a plurality of bounce springs positioned along the circumference ate path of that portion of the shutter blade which engages the bounce springs. These bounce springs are adjusted into and out of this path so as to reverse the shutter blade when in the path but to allow the shutter blade to when the bounce springs are out of the path. These bounce springs are preferably moved into and out of the relates to improveture, preferably comprises a disc having a plu- 7" rality of openings arcuately spaced on the disc. The disc is mounted for pivotal movement within the shutter housing so that the various openings carried by the disc may be successively brought into coaxial relationship with the lens system. 1 c cam, mentioned above, for controlling the operative and inoperative positions of the various bounce springs, is preferably formed as a unitary part of the diaphre gm so that, when the diaphragm is rotated to position a desired opening adjacent the lens system, the cam is likewise rotated to move the various bounce springs into and out of their shutter bladeengaging positions.

Associated with the above-described shutter and diaphragm assembly is a time exposure latch which can be rendered operative to hold the shutter blade in a position where the exposure aperture is uncovered 2s long as the tripping lever is held in its tripping position. There is also included a novel flash bulb firing switch which is actuated, in a preferred form of the invention, by the kicker after the kicker has initiated rotation of the shutter blade.

Referring now to the various drawings, where like numbers refer to like elements in the different fi ures, the preferred constructional features of the present invention will be apparent. Referring particularly to Figs. 1 and 2, the shutter and diaphragm assembly is includes a front housing l2 and a rear housing it. Suitably mounted in these two hou ings is a camera lens system comprising a front lens it, a middle lens it and a rear lens 2 Positioned behind the front lens i5 and in front of the middle lens is is a diap ra m 22 and a shutter blade 25. This shutter blade is rotatably mounted on a suitable bearing. generally indi ated at this bearing preferably having a m nimum amount of friction. Referrin now more partic larly to Fig. 1., it can be seen that there are provided a plurality of bounce springs 23, it, 32 and carried by the housing l2 and positioned adjacent the path of travel of a portion oft e shutter blade during rotation of the shutter blade around its bearing as a center. For initiating rotation of the shu ter blade there is provided a kicker, generally indicated at 36, this kicker bein urged in a clockwise direction by a ki ker spring 38, kicker to being held in the position shown by a latch (it. For releasing the latch from the kicker 36 there is provided a tripping lever shown generally at For normally holding the shutter blade the position shown there is provided a retaining means is comprising, in a preferred form, a magnet 66.

A brief discussion of the operation of the shutter diaphragm assembly described above will be helpful in en understanding or the detailed disclosure of the various elements to follow. In the use of the above-described modification of the invention, the tripping lever is actuated to cause the movement of the kicker 35 into posi tion adjacent a log til on the shutter blade. Con: tinned movement of the tripping lever releases the latch to from the kicker, thus permitting the spring iii, to rotate the kicker rapidly in a clockwise direction. This rotation of the kicker is transmitted to the shutter blade which is rotated rapidly in a counterclockwise direction around its pivot 25. Rotation of the shutter blade in this counterclockwise direction uncovers an exposure opening id in the diaphragm 22, opening is being aligned with the lens system. This rotation of the shutter blade continues until lug so strikes the first bounce spring which is in the path of the shutter. As shown in Fig. i, bounce spring 2% is in this path so that this is the bounce spring which reverses the direction of rotation of the shutter and thereupon returns the shutter blade to the position shown in Fig. l. The magnet to engages and holds the shutter blade in this initial position, the diaphragm opening is, aligned with the lens axis, being again covered by the shutter blade.

Construction of the shutter blade and magnet Referring now more specifically to the construction of the shutter blade, it can be seen that the preferred modification thereof includes the opaque blade 2% and a suitable counterbalance tlil, those portions being preferably connected together at the shutter blade axle 5%. As seen best in Fig. 2, the axle has one bearing 52 carried by the front housing i2 and another bearing 5% which is carried by a cross bridge That end of the shutter axle 53 associated with the second bearing is preferably connected bearing Ell by means of a spring Adjacent one end of the shutter blade and counterbalance assembly, there is provided an impulsereceiving and bounce spring-engag g portion. This portion preferably comprises the lug 55%, the left (Fig. 1) side of which to receive a rotating impulse from the kicker and the right side of which engages the various bounce springs. A second lug 52 is somewhat rcuately spaced from the kicker-engaging lug corn prises a magnetic portion adrpted to engage the magnet lit when the shutter is in, or returned to, the position shown in Fig. 1.

The magnet lii, which normally shutter blade in the position shown, mounted in a magnet holder ll, this magnet holder also supporting a block so or yielding material, such as sponge rubber, in shock-absorbing relationship to the magnet so as to permit the magnet to move slightly and thus absorb the kinetic energy of the shutter blade when this shutter blade returns to its position of rest.

The bounce spring In a preferred form, bounce springs 23, so, 32 and as, mentioned previously, comprise portions 2%., tiia, 32a and E la, respectively, which are adapted to engage the shutter blade lug so during its rotation. The bounce springs also coinprise resilient portions 28?), sub, 32b and 3%, these portions being preferably arranged so that their respective blade-engaging portions etc. travel in a path which is substantially tangential to the path of shutter blade lug so, both when absorbing energy from the shutter blade and when transmitting energy to the shutter bla Each of bounce springs and also respectively includes a cam-engaging portion 280, tile and 320. Since bounce spring as is not moved by a cam it does not contain any carnengaging portion. For predeterminedly positioning the bounce springs, the shutter housing pref- 34. As can be seen best from an examination of Fig. 2, the outer end of each bounce spring is relatively narrow, thereby being readily easily deflected by the shutter blade. However, the remaining portions of each bounce spring (for example, portions 32c, etc.) are relatively wide as seen in Fig. 2. This construction serves several very useful functions. In the first place, it imparts rigidity to the bounce springs. In the second place, these wide portions are made wide enough so that they extend between the front housing and the rear housing and may thereby hold the bounce springs against movement with respect to support lugs 64 by engaging the two hOllSillg members. Lastly, these wide portions of the bounce springs may be used to hold the diaphragm 22 in position.

The diaphragm lhe diaphragm, which is generally indicated at comprises a disc-dike element mounted for rotation around its axis and with its axis parallel to the lens axis. The diaphragm has a peripheral portion in one plane and a central portion in another plane, the various diaphragm exposure openings or apertures being preferably formed in the central portion. As seen best in Fig. l, the peripheral portion it has a number of gear teeth on the circumference thereof. Diaphragm 22 mounted for rotatable movement by means of a boss '14 (Fig. 2) preferably formed in the front housing l2, this boss being engaged by a forwardly extending diaphragm flange 7E. Diaphragm 22 also includes a central portion 78 having a plurality of openings 79 formed therein. The center of each opening 78 is preferably aroua tely spaced by an equal distance from the center of each adjacent opening I5. By rotation of the diaphragm 22, the openings 19 may be successively predeterminedly aligned with the of the lens system. For rotating the diaphragm there is provided a gear 82 meshing with the diaphragm gear teeth This gear 8!) is mounted on a shaft 83, as is cam 82. Thus cam 82 retates as a unitary structure with the gear 80. A cam-engaging detent spring 84 is positioned to engage a cam detent notch 85 associated with the gear cam 82. A knurled disc 86, carried by the shaft preferably extends to the exterior of the shutter housing to enable the camera user to rotate the gear 38.

The diaphragm 22 also includes a cam surface portion on which is formed at the junction between the peripheral portion 70 and the central portion 18. This cam surface portion 50 engages the portions 25c, c and 320 of the corresponding bounce springs and serves to move these bounce springs out of shutter blade-engaging position. With the cam surface portion 32 in the position shown in Fig. 1, all of the bounce springs 28, 32 and M are in their shutter blade-intercepting position. When the diaphragm 22 is rotated in a counierolockwise direction through i one-eighth of the diaphragm circumference) the follower portion 2 30, of bounce spring 23, is engaged and the engaging portion 28a of this bounce spring is moved out o! the path of the shutter blade. When this diaphragm 22 is now rotated another 45, the cam portion Etc of bounce spring 36 is engaged and moved outwardly, thereby moving engaging portion 30a of this bounce spring out of the path of the shutter blade. A further 45 rotation of the cam will move portion 32a of bounce spring 32 out of the path of the shutter blade. When the cam at is in this last position and the shutter blade is rotated by the kicks 3a, the shutter blade will swing through almost a. 300 arc of travel until lug 5-3 engages portion 34a of bounce spring 34. This last-mentioned position of the cam 90 thus gives the longest time during which the exposure aperture is uncovered by the shutter.

In a preferred form of the invention the diameter of the gear bears the ratio to the diameter of the diaphragm gear 12, where a: is the number of cam notches 35 and n is the number of diaphragm openings 12?. Since there is preferably one cam notch and there are eight diaphragm openings 19, the gear to is oneeighth of the diameter of the diaphragm gear 72. With this arrangement, one complete rotation of the gear 80 rotates the diaphragm 45 and thus moves one opening 19 in the diaphragm out of alignment with the lens system and moves the next opening 19 into alignment with the axis of the lens system. In this way, the cam notch 35 indicates to the user of the shutter assembly that one of the diaphragms is in proper position. For ascertaining the relative angular position of the diaphragm, and thus ascertaining which of the openings 79 is aligned with the lens axis, a window S2 is provided in the front housing. This window 92 is so arranged that indicia printed on the front surface of the peripheral portion it? of the diaphragm may be successively brought into view. It will be apparent that these indicia conveniently run from 1 through 8 (the number of openings 19), these indicia corresponding to predetermined light values, Thus, for example. a number may correspond to a maximum size of opening 19 plus the longest exposure time. Number 2 may correspond to a maximum size of exposure opening and a somewhat shorter ex posure time, etc. It should be understood that the above-described gear ratio of 8 to i is of course subject to considerable modification. For example, if nine openings l9 were provided, the gear ratio would preferably be 9 to 1. If two notches 85 were provided, the gear ratio could be halved, as explained above.

Tripping lever, kicker assembly and kicker latch The kicker, tripping lever and kicker latch are shown best in Figs. 1, 3 and 4.. In a preferred form, kicker 36 is carried by an arm I i 0 pivotally mounted with respect to the housing. Spring means bias this towards the shutter blade and also bias the kicker in its impulse-imparting direction. The kicker latch holds the kicker against the bias of the spring means and the tripping lever, through the kicker, holds the kicker-carrying arm against its bias. Thus the kicker s held against rotation and also spaced from the shutter blade. In a preferred form, a cooking spring is employed with the tripping lever 42 for overcoming the bias of the above-mentioned bias spring means. In Fig. 1 the various elements are shown in the position as normally held by the cocking spring, in Fig. 3 the elements are shown with the kicker just about to rotate the shutter blade and in Fig. l the kicker has been released and has rotated the shutter blade. As seen in these figures, the tripping lever 42 is mounted for pivotal movement around a pivot pin it. Lever #2 comprises an actuating portion Hi2, which extends to the exterior of the shutter housing, and a latch release arm its. Dn the end of arm its there is provided a first surface portion see which is adapted to engage the edge of latch at so as to move latch it with respect to the kicker 3t and thus release the kicker. Arm use also includes a second surface portion Hi3 which is adapted to engage a portion of the kicker as will be hereinafter described. The kicker 36 is secured, by means of a pivot pin its, to an arm Hi3 which is preferably pivotally mounted on the same pivot pin its which mounts the tripping lever 32. The kicker 35 preferably includes two arms, one of these arms H2 being that por tion of the kicker which is adapted to engage the lug 65 on the shutter blade. The other arm lid serves the dual function of being engaged by the tripping lever surface Hi3 and also of actuating the flash contact in a manner to be described hereinafter. Kicker arm l l2 has a tab 9 it thereon which engages latch 553. The kicker 35 also includes a hook M8 to which is secured the kicker spring 38, The other end of the kicker spring 38 is secured to a block l2c, this block in turn being supported by a screw 822 for adjusting the position of the block and thereby the tension on the spring Tripping lever ii. also has associated therewith a relatively strong cocking spring one end of which bears against a turned-down tab E26 preferably punched from tripping lever 42. The other end of the cocking spring i213 is received in a depression are conveniently formed in the front housing l2. An internal cylinder i115 serves to reinforce the cocking spring are.

For limiting rotation of the kicker-carrying arm lid around the pivot pin its, there are provided two stops, one of these stops being indicated at I34 and the other being indicated at 535, the kicker-carrying arm ill being shown in Fig. l as abutting against stop ltd, this being the normal position for the various elements at rest.

The latch is is preferably pivotally mounted by means of a pivot pin ass, the outer end of the latch including a hook it! which engages the tab i it on arm 3 52 of kicker 3t and thus prevents clockwise rotation of the kicker around its pivot. A bias spring E32 is provided adjacent the pivotal mounting of the latch ll! so as to normally urge the latch in clockwise direction around its pivot pin, a stop its being provided for limiting this rotation of the latch to.

The flash synchromecr The flash synchronizing mechanism is preferably so arranged with respect to the kicker that a portion of the kicker, after it has transmitted rotational movement to the shutter blade, causes the closing of the flash bulb firing switch to initiate the flash. In a preferred form of the invention, the various elements of the flash synchronizing mechanism are so arranged that they absorb a certain amount of the kinetic energy of the kicker and also provide positive closing of the flash bulb circuit without danger of reopening of the circuit before the flash is completed. This flash synchronizing mechanism comprises a flash contact i l? which, when it engages a ground contact M3, energizes the flash bulb. The flash contact M2 is carried on the end of a resilient conducting arm Hi l, this arm having an inclined surface H56 which is engaged by arm lid of the kicker 36 after the kicker 36 has transmitted its kicking impulse to the shutter blade. Inclined surface M6 makes a slight angle with the tangent to the path followed by the end of kicker arm l 14, thereby preventing direct normal impact of arm H4 on surface Hit and consequently eliminating bouncing of the arm H l after initial contact with surface use. The conducting arm its is suitably connected to the inner end of a flash connector receptacle 848 of conventional type, suitable insulation being provided between flash contact arm use and the shutter housing.

r The operation of the shutter With the various elements of the shutter and diaphragm assembly in the position shown in Fig. 1, all the parts thereof are at rest, the shutter being cooked and ready for use. During operation of the shutter, the actuating portion Hi2 of the tripping lever M is engaged by the camera user and rotated in a clockwise direction around pivot pin we, thus compressing the cocking spring i2 5. This clockwise rotation of tripping lever d2 moves the latch release arm lu l towards the shutter blade 24. As arm was moves, the kickerengaging surface its carried thereby also moves towards the shutter blade, thus allowing the kicker spring 38 to rotate the kicker-carrying arm i it in a clockwise direction around pivot pin its from the position shown in Fig. 1 to the position shown in Fig. 3. In Fig. 3 it can be seen that kicker arm l l2 has been moved into position behind shutter blade lug fill so as to be able to transmit a kicking impulse to the shutter blade when the kicker is released. When the kickercarrying arm HE engages the stop l3 l, this arm can no longer rotate. Continued clockwise rotation of the tripping lever '22 disengages the surface lilt from the kicker arm lid and moves the latch-engaging surface E06 into engagement with the latch QB. This position of the various elements is shown in Fig. 3. At this point, the kicker is still held by the hook I3! on the end of latch it}, the kicker being held by the latch against the bias of spring 3t. It should also be noted that, during the above-described movement of the elements, latch 40 has been rotated in a counter clockwise direction around its pivot pin its against the bias of its spring E32.

Continued clockwise rotation of the tripping lever d2 past the position shown in Fig. 3 causes the latch-engaging surface its to lift the latch so so that the hook l3i thereon clears the tab H6 on kicker arm H2, thereby releasing the kicker for rapid rotation by kicker spring 38. As the kicker rotates, arm l l2 thereof strikes the left side of lug 6%, as seen in Fig. 3, and imparts asharp impulse to lug lit, the kicker arm being disengaged from lug so after the lug to has moved through a small predetermined arc. The impulse applied by the kicker arm H2 to the shutter blade 1s amply strong to disengage the lug 52 from magnet 8 and to rotate the shutter blade 25 in a counterclockwise direction around its bearing 25. Rotation of shutter blade 24 continues till the right-hand side of lug 6t strikes the first bounce spring positioned in the arcuate path of travel of lug 6B. This bounce spring, which would be spring 28 with the dia hragm cam M in the position shown in Fig. lireturns the shutter blade 24 to its initial position over- 9 lying the diaphragm aperture. As the shutter blade returns, the magnetic portion 63, carried by lug 62 thereon, strikes magnet 46, this magnet moving slightly under this impulse.

thereby avoided.

When the kicker rotates during its application of the kicking impulse to lug arm I04 are shown in dotted lines.

fact that the end of kicker arm I I 4 strikes the inclined surface I45 with a grazing motion there impact which might cause arm H4 in its movement. Therefore there Due to the When the actuating portion of the tripping lever is released by the camera user at the end of an exposure, the cooking spring i2 5 rotates the tripping lever 62 in a counterclockwise direction around the pivot pin ltlil. This moves the kickerengaging surface 5 be away from its l position to its Fig. 1 position. It should be noted that spring 33, due to its arrangement with respect to the two pivots i555 and i has a relatively strong bias preventing rotation of kicker 35 in a counterclockwise direction around pivot I59 and a rather weak bias preventing a counterclockwise rotation of kicker-carrying arm Iii around pivot Hill. Therefore, the first part of the counter clockwise movement of kicker engaging surface I08, associated with the tripping lever 42, rotates kicker-carrying arm H9 in a counterclockwise stop I35. During this rotates in a counterclockwise direction, rotated in a clockwise direction around its pivot I38 by means of bias spring 032 until latch it hits stop i33. Furcounterclockwise movement of the kickerengaging surface ltd rotates the kicker 35 around its pivot it. Since the kicker-carrying arm H0 is now in the Fig. 1 position the rotation of kicker 3t swings the end of kicker arm H2 in an are which is spaced from the kicker lug 66. As the end of this arm I it swings, tab IIG carried thereby lifts the latch it till the position of Fig. l is reached, whereupon the hook 53' moves into the latched position.

The time exposure latch best in Figs.

rendered ineffective after each use so that the camera operator will not inadvertently make a second time exposure instead of an instantaneexposure. As seen in Fig. 1-, the tripping lever 52 also includes an arm for rating the time exposure latch. carries, near its outer end, a pivot pin which rctatably supports a pawl Hi l. A bias spring its urges the pawl H'i l in a clockwise direction around pivot l The time exposure latch, indicated generally at 168, comprises a pivot pin ill rotatably supporting a movably mounted member llZ, this member carrying an ear H4 and a cam surface I75. At the other end of member H2 there is provided detent 4 l3 which adapted to engage one of two depressions in a detent spring ltd suitably connected to the shutter housing l2. The time exposure latch it??? also includes a econd member 132, this second member being pr ably integral with member 1'52 and having a hole at one end thereof (see Fig. 5). This ho s adapted to receive the inner end of a ob 3 3 which preferably extends through th front shutter housing I2 so as to be operable f om the front of the shutter housing. Knob ii -i is a a pivot pin I 8-3. For forming the shut engaging portion of the time exposure there is provided a pair of springs Spring 88 is a relatively stron spring and the spring I59 is a relatively weak 'ing. As can be seen, the outer end of strong spring iii-i5 is sub stantially normal to the path of travel or" shutter blade lug fill. while weal: spring i is nearly tangential to the path. of travel of the lug hen a time exposure is desired, the time latch knob Ilifi is moved to cause a rotation of the two members $82 and I72 around the pivot pin in a counterclockwise direction. This rotation swings the springs IE8 and 3% into the arcuate path followed by the shutter blade lug til. the shutter blade 24 is rotated, the lug {58 engages weak spring IQS with a grazing motion and sweeps past spring Is -ll till it hits spring 38 and rebounds therefrom. As the blade rebounds it strikes the outer end of spring l and is held \JU thereby as long as the tripping lever 42 is held in its tripped position. While the hair spring has normally no appreciable eiiect on the shutter blade rotation, it is biased by the counterclock- Wise rotation of the shutter blade and thus tends to rotate the shutter blade in a clockwise direction when the shutter blade is held by the spring I90. When the tripping lever 2 released at the end of the time exposure, the cooking spring I24 rotates the tripping lever in a counterclocluvise direction, thus moving pawl-carrying arm I50 also in a counterclockwise direction. As a result of this movement, pawl E64 engages ear il and rotates member I12 in a clockwise direction. This rotation moves the detent I 723 from the outer notch in detent spring its to the inner notch. As detent IlB enters the inner notch in detent spring I80, the inclined surface of this notch until it is comthis notch. This completes the rotation of the member H2, thereby moving the outer end of spring I99 radially with recite the lug S0 and disengaging this end or spr from the lug 6D. The hair spring 52 new 0 the shutter blade 2 in a clockwise direction to its initial position where it is h ld by eng ment of the magnetic portion 33 with the net 46.

During the latter of member I12, the member I12,

g is ate part of the clockwise rotation the cam surface I75, carried by engages a corresponding surface on the pawl ltd and rotates pawl its in a counterclockwise direction around its pivot int against the bias or" spring ihe time exposure latch 568 is now in a position where it is ineffective to stop the rotation of shutter blade 2d until this time latch is manually reset. When the time latch its is in this ineffective position, the operation of the tripping lever 42 does not afiect the time latch since the cam surface H6, on the member H2, holds the end of pawl ltd so that it cannot engage the ear lid. It should be noted in this connection that, when the time latch member H2 is rotated to its shutter blade-engaging position, the cam surface H6 bears on the corresponding surface of pawl Hi l and rotates pawl its to the the left until the ear Ht has passed the outer end of pawl N34.

While a preferred form of the invention has been described above, numerous modifications thereof may be made without departing from the scope of the invention. For example, the lug fit on the shutter blade may include a resilient portion adapted to engage the reversing members. In this case the bounce springs 23, 30, 32 and 3 could be replaced by relatively rigid reversing members. Additionally, the block 12s for adjusting the bias on kicker spring 3i? may be made widely adjustable so as to increase the number of possible exposure times without increasing the number of bounce springs. Similarly, the spring 38 may be replaced by two springs, one of these being a weak spring for exerting a counterclockwise bias to arm i it around pivot pin 1% and the other being a strong spring for exerting a clockwise bias to kicker 38 around pivot pin Hi9. In still other modifications of the invention, the flash circuit contact arm l l l may be arranged so as to be contacted by kicker arm l i2 rather than by kicker arm lid, while the lugs 5d and 62 may be placed on the counterbalance portion of the shutter blade. Numerous other modifications of the invention will be apparent to those skilled in the art in view of the teachings herein.

Since certain changes may be made in the above apparatus without departing from the scope of the invention herein involved, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. A camera shutter comprising a housing, means for supporting a shutter blade in operative relation to an exposure aperture in said housing, said shutter blade normally covering said aperture and being supported for rotary movement to a position where said aperture is uncovered, means for imparting an aperture-uncovering rotation of predetermined speed to said shutter blade, means for reversing rotation of said shutter blade to cause said shutter blade to return to aperture-covering position, said last-named means comprising a bounce spring, said spring including a shutter blade-engaging portion, a resilient portion arranged to permit said firstnamed portion to move in a direction substantially tangential to the path followed by a part of the shutter blade, another portion for engaging a support and a cam-engaging portion, a cam for moving said shutter blade-engaging portion of said spring with respect to said path of said shutter blade, said support-engaging portion positioning said spring so that said cam-engaging portion is held in resilient contact with said cam in substantially all positions of said cam, and a rotatably bounce spring being arranged to engage one surface of said diaphragm and prevent axial movement of said diaphragm.

2. A camera shutter comprising a housing, means for supporting a shutter blad in operative relation to an exposure aperture in said housing, said shutter blade normally covering said aperture and being supported for rotary movement to a position where said aperture is uncovered, means for uncovering rotation of predetermined speed to said shutter blade, means for reversing rotation of said shutter blade to cause said shutter blade to return to aperture-covering position, said lastnamed means comprising a bounce spring, said spring including a shutter blade-engaging portion, a resilient portion arranged first named portion to move in a direction substantially tangential to the path followed by a part of. the shutter blade, another portion for engaging a support and a cam-engaging portion, and a cam for moving said shutter blade-engaging portion of said spring with respect to said pathof said shutter blade, said support-engaging portion positioning said spring so that said camengaging portion is held in resilient contact with said cam in substantially all positions of said cam. said housing comprising a front and a rear portion, said support being carried by one of said housing portions, said other housing portion having a cooperating portion for preventing dislodgement of said bounce spring from said support.

3. A camera shutter comprising a housing, means for supporting a shutter blade in operative relation to an exposure aperture in said housing, said shutter blade normally covering said aperture and being supported for rotary movement to a position where said aperture is uncovered, means for imparting an aperture-uncovering rotation to said shutter blade, means for controlling the time during which said shutter blade is in aperture-uncovering position, and a diaphragm for controlling the effective size of said aperture, said diaphragm comprising a disclike element mounted for rotation around its axis and with its axis parallel to an associated lens axis, said element having a peripheral portion in one plane and a central portion in another plane, said planes being parallel and spaced from each other along the lens axis, said two portions being joined by a third surface portion which extends between said two planes in a direction substantially parallel to said lens axis, difierent arcuate portions of said third surface portion being predeterminedly and differently spaced from the diaphragm axis so as to serve as a cam upon rotatron of said diaphragm, said controlling means including a cam-engaging portion, whereby said cam is effective to selectively control said timecontrolling means.

i. A camera shutter comprising a housing, means for supporting a shutter blade in operative relation to an exposure aperture in said housing, said shutter blade normally covering said aperture and being supported for rotary movement to a position where said aperture is uncovered, means for imparting an aperture-uncovering rotation to said shutter blade, means for controlling the time during which said shutter blade is in apertureuncovering position, and a diaphragm for controlling the eiiective size of said aperture, said diaphragm comprising a disclike element mounted for rotation around its axis and with its axis mounted diaphragm, a portion of said imparting an aperture to permit said i two planes in a direction substantially parallel to said lens axis, different arcuate portions of said third surface portion being predeterminedly and diiierently spaced from the diaphragm axis so as to serve as a cam upon rotation of said diaphragm, said controlling means including a camengaging portion, whereby said cam is efiective to selectively control said time-controlling means, said diaphragm including a flange near its axis, said housing carrying a boss for engaging said flange.

5. A camera shutter comprising a housing, means for supporting a shutter blade in operative relation to an exposure aperture in said uncovered, means for imparting an apertureuncovering rotation to said shutter blade, means for controlling the time during which said shutter blade is in aperture-uncovering position, a diaphragm for controlling the effective size of said cured to and rotatable with said gear and having at least one detent portion, and a detent adapted to engage said detent portion in order to fix said cam and said diaphragm in predetermined rotational positions, the diameter of said gear bearing the ratio to the diameter of said diaphragm where a: is the number of detent portions on said cam and n is the number of diaphragm apertures, the center of each said diaphragm aperture being arcuately spaced from the center of its adjoining apertures by an amount equal to 6. A camera shutter comprising a housing, means for supporting a shutter blade in operative relation to an exposure aperture in said housing, said shutter blade normally covering said aperture and being supported for rotary movement to a position where said aperture is uncovered, means for imparting an apertureuncovering rotation to said shutter blade, means for controlling the time during which said shutter blade is in aperture-uncovering position, a diaphragm for controlling the effective size of said aperture, said diaphragm comprising a disclike element mounted in said housing for rotation around the axis of said diaphragm and with said axis parallel to an associated lens axis, said disc-like element having a cam surface cooperating with said shutter time controlling means whereby the rotational position of said disc-like element determines the time during which said to rotate said diaphragm, a cam secured to and rotatable with said gear and having at least one detent portion, and a detent adapted to engage said detent portion in order to fix said cam and said diaphragm in predetermined rotational positions, the diameter of said gear bearing the ratio to the diameter of said number of detent portions on said cam and n is MURRY N. FAIRBAN K.

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